[目的]嫩度是肉品质量的首要指标,其影响牛肉的消费和商业价值;寻找合适的嫩度指标,快速、无损、客观地预测牛肉嫩度一直是肉品学研究的热点之一。[方法]本文基于机器视觉技术和图像处理方法,分割牛肉图像的肌间结缔组织区域,提取肌间...[目的]嫩度是肉品质量的首要指标,其影响牛肉的消费和商业价值;寻找合适的嫩度指标,快速、无损、客观地预测牛肉嫩度一直是肉品学研究的热点之一。[方法]本文基于机器视觉技术和图像处理方法,分割牛肉图像的肌间结缔组织区域,提取肌间结缔组织的特征参数,运用统计学方法关联该特征参数和熟肉剪切力值,结合经过专门训练的评级小组的分级,采用Stepwise多元线性回归(Stepwise-MLR)建模,对牛肉嫩度进行预测和分级。[结果]70个样本图像的结缔组织特征数据全部用于训练模型,采用留一法交叉验证(Leave-one-out cross validation)测试模型,验证模型的牛肉嫩度判别系数(R^2)为0.857,剩余标准误差(residual standard error,RSEC)为6.453;将牛肉分为嫩、中等、老3个等级,全部预测集的总体等级预测正确率为88.57%。[结论]肌间结缔组织特征是预测牛肉嫩度的重要指标,本文所用的软硬件方法对牛肉嫩度的快速、无损、客观预测和分级具有一定的实用价值及指导意义。展开更多
miRNAs are a class of small, single-stranded, non-coding RNAs that perform post-transcriptional repression of target genes by binding to 3＇ untranslated regions. Research has found that miRNAs involved in the regulat...miRNAs are a class of small, single-stranded, non-coding RNAs that perform post-transcriptional repression of target genes by binding to 3＇ untranslated regions. Research has found that miRNAs involved in the regulation of many metabolic processes. Here we uncovered that the beef quality of Angus cattle sharply diversified after acute stress. By performing miRNA microarray analysis, 13 miRNAs were significantly differentially expressed in stressed group compared to control group. Using a bioinformatics method, 135 protein-coding genes were predicted as the targets of significant differentially expressed miRNAs. Gene Ontology （GO） term and Ingenuity Pathway Analysis （IPA） mined that these target genes involved in some important pathways, which may have impact on meat quality and beef tenderness.展开更多
We present a rapid system for predicting beef tenderness by mimicking the human tactile sense. The detection system includes a FS pressure sensor, a power supply conversion circuit, a signal amplifier and a box in whi...We present a rapid system for predicting beef tenderness by mimicking the human tactile sense. The detection system includes a FS pressure sensor, a power supply conversion circuit, a signal amplifier and a box in which the sample is mounted. A sample of raw Longissimus dorsi (LD) muscle is placed in the measuring box; then a rod connected to the pressure sensor is pressed into the beef sample to a given depth; the reaction force of the beef sample is measured and used to predict the tenderness. Sensory evaluation and Warner-Bratzler Shear Force (WBSF) evaluation of samples from the same LD muscle are used for comparison. The new detection system agrees with established procedure 95% of the time, and the time to test a sample is less than 5 minutes.展开更多
文摘[目的]嫩度是肉品质量的首要指标,其影响牛肉的消费和商业价值;寻找合适的嫩度指标,快速、无损、客观地预测牛肉嫩度一直是肉品学研究的热点之一。[方法]本文基于机器视觉技术和图像处理方法,分割牛肉图像的肌间结缔组织区域,提取肌间结缔组织的特征参数,运用统计学方法关联该特征参数和熟肉剪切力值,结合经过专门训练的评级小组的分级,采用Stepwise多元线性回归(Stepwise-MLR)建模,对牛肉嫩度进行预测和分级。[结果]70个样本图像的结缔组织特征数据全部用于训练模型,采用留一法交叉验证(Leave-one-out cross validation)测试模型,验证模型的牛肉嫩度判别系数(R^2)为0.857,剩余标准误差(residual standard error,RSEC)为6.453;将牛肉分为嫩、中等、老3个等级,全部预测集的总体等级预测正确率为88.57%。[结论]肌间结缔组织特征是预测牛肉嫩度的重要指标,本文所用的软硬件方法对牛肉嫩度的快速、无损、客观预测和分级具有一定的实用价值及指导意义。
基金supported by Maryland Agricultural Experiment Station and Jorgensen Endowment Funds
文摘miRNAs are a class of small, single-stranded, non-coding RNAs that perform post-transcriptional repression of target genes by binding to 3＇ untranslated regions. Research has found that miRNAs involved in the regulation of many metabolic processes. Here we uncovered that the beef quality of Angus cattle sharply diversified after acute stress. By performing miRNA microarray analysis, 13 miRNAs were significantly differentially expressed in stressed group compared to control group. Using a bioinformatics method, 135 protein-coding genes were predicted as the targets of significant differentially expressed miRNAs. Gene Ontology （GO） term and Ingenuity Pathway Analysis （IPA） mined that these target genes involved in some important pathways, which may have impact on meat quality and beef tenderness.
基金supported by the Key Project of Science and Technology Foundations of Jilin Province of China (Grant No.20060217)the Research Foundation for the Talents by the People's Government of Jilin Province
文摘We present a rapid system for predicting beef tenderness by mimicking the human tactile sense. The detection system includes a FS pressure sensor, a power supply conversion circuit, a signal amplifier and a box in which the sample is mounted. A sample of raw Longissimus dorsi (LD) muscle is placed in the measuring box; then a rod connected to the pressure sensor is pressed into the beef sample to a given depth; the reaction force of the beef sample is measured and used to predict the tenderness. Sensory evaluation and Warner-Bratzler Shear Force (WBSF) evaluation of samples from the same LD muscle are used for comparison. The new detection system agrees with established procedure 95% of the time, and the time to test a sample is less than 5 minutes.
